Insolubilization of photographic antistatic coatings



United States P31611110 3,072,484 INSOLUBILIZATION. F PHOTOGRA'PHIC ANTI- STATIC COATINGS Cornelius C. Unruh and Calvin S. Garber, Rochester,

N.Y., assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey I No Drawing. Filed Feb. 12, 1959, Ser. No. 792,700

' 12 Claims. (CI. 96-87) This invention relates to the treatment of photographic film. More particularly this invention concerns insolubilizing antistatic coatings, a method for preparing such coatings, particularly such coatings on color film, as well as the improved film products having insolubilized antistatic layers thereon.

As set forth in detail in Thompson and Lyons U.S. patent application Serial No. 529,376, now Patent No. 2,882,157, it has been known in general that in the motivating, handling, winding, unwinding and the like operations applied to webbed materials, there may be encountered problems of friction, static and the like. This is particularly true in handling photographic film. Hence, it has been the practice to apply antistatic coatings, or to use other expedients for facilitating the handling and other operations as applied to such product.

Photographic film presents particular problems for several reasons. For example, photographic film being comprised of a relatively, nonporous base or support, presents problems of finding treating agents which will suitably adhere thereto. Thert is the particular problem of employing coatings which not only accomplish the result of reducing'static, but which do not adversely affect the sensitivity of the light-sensitive layers on the photographic film. With color film there are still further problems. Color film contains not only the light-sensitive compounds, but may contain numerous other components such as couplers, dyes and the like. Although certain antistatic materials heretofore known do not adversely affect silver salts, there may be situations where with the more complex make-up of color film, hazing or other adverse influence on color constituents can occur. Also, color film in its manufacturing and processingmay be subjected to several and dificrent types of steps and liquid applications. 7 A 'In the Thompson and Lyons" patent aforementioned there has been disclosed a very useful film backing layer: comprised of a type compound referred to as a polymerized quaternized dialkylaminoalkyl acrylate compound.

Such type of backing, as well as certain other polymeric types of backing as will be described hereinafter, are useful over'quite a wide range of operation and provide a good antistatic layer. However, ithasbeen found that under some conditions of operation certain problemsmay arise. For. example, at highliumidities and temperatures the aforementioned types of backings can become tacky therefore presenting the problem of the film sticking upon itself' if tightly rolled. In some instances the coatings may exhibit. a tendency to wash oif during film processing or the like.

It is'apparent therefore that the development of a coating which is insolubilized to some extent and'which may be applied tophotographic filnifor facilitatingthe winding andunwinding thereof, as. wellas f acilitating-other operations represents a highly desirable result. After extended investigation We havefound that quaternizedor partially? quaterni'ze d polymericchemical compounds which will. be described. detail hereinafter,-may be treated in. certain .ways to. insolubilize them; andthe-film backings there'ofl, to provide backin-gs having a'- wider range of usefulness. H I p This invention has for one object to'provide a new insolubilized backing for photographic film, and particularly photographic color film. Another object is to provide improved polymeric backing material on photographic film. Still another object is to produce photographic film, particularly color film, having a backing which contains a polymeric quaternized compound in the backing and is relatively non-tacky and which will better withstand certain processing treatments. A particul ar object is to apply a backing to color film which does no'tfadversely afiec't the color layer even when the backing and color layer are wound in tight contact. Still another object is to provide a hacked color film which exhibits the advahf; tages of being relatively static-free and non tacky. Still a further object is to provide formulations of polymer coatings wherein cross-linking has occurred and to prov-ide a. material particularly adapted to coat onto. color films as backings. Other objects will appear hereinafter.

The present invention is particularly useful as applied to polymerized quaternized dialkylaminoalkylunsaturated esters as described in Thompson et al. patent, aforemen; tioned. The application of the cross-linked backings or the present invention may take place at most any time in the manufacture of sensitized film product. However, We usually prefer to apply our cross-linked backing at the early stages of manufacture inasmuch as our improved backing of the present invention appears to readily withstand washing and the like steps.

Inasmuch as the film structure, method of applying, the coatings and the like are the same as disclosed in detail in the Thompson and Lyons patent aforementioned; extended description herein appears unnecessary. It ap pears sufiicient to point out that the base or support may be comprised of any of the film base materials usedin; dustrially. We frequently employ a support comprised of cellulose acetate. However, other support material may be used. The support carries the light-sensitive layer, which may be a color layer, on one, side and the antistatic backing on the other. The exact make-up of the light-sensitive layer is not a limitation upon the present invention. It is suificient to point out that the color section in general will comprise a plurality of separate-layers. These separate layers in addition to containing sensitive silver salts may, and frequently will, contain various other components such as sensitizers", couplers, dyes and the like. For further details concerning the color section, ref erence may be made to US. Jelley et a1. Patent 2,322,027, patented June 15,1943. Since this patent describes in detail the composition of various color layers, the composition of various couplers, as well as" procedures for making and applying such color layers, description herein of such' details does notappear to be required. 7

Reference ,is' now made to the backing of the present invention, the particular composition thereof and method of application to fil'rn. ,In thebroader phases of the present invention, we have found that certainpo yrrreriz ed; quaternized compounds" in the presence of cra s linking a'gents may be applied to color film support, thereby forming a'backing layer oii color film,and onto vanes; other types of photographic film as will be describedhere inafter, which backing exhibits improved properties non-tackiness, resistance to washing and the like. In the broader aspects of the presentinvention we have found that varous polymeric quaternary antistatic coatings may be improved-by the cross-linking treatments of the present invention which 'yvill be described in' de'tail Inquaternized or part 1y quateriii'zedl dialkylaniinoayl actuate-er nietha'crylate polymers of the type described in the Thompson and Lyons patent aforementioned We have found that anefiectiveway is to'coatdilute solution of an incompletely quaternized tertiary amine containing polymer, the solution containing a cross-linking agent, such as a bifunctional or polyfunctional quaternizing agent, capable of reacting with the unquaternized .tertiary amino groups, thus insolubilizing the polymer and also extending its conductivity by virtue of added fcharged groups. Eminently suitable cross-linking agents are exemplified by polyepoxides (e.g., diglycid ether), xylylene dibromide, bis-alkylor bis-arylsulfonoxy alkanes, alkenes or alkynes.

The cross-linking agent may advantageously be added to the dilute solution of the incompleted quaternized tertiary amino polymer just prior to coating. As the coating dries and during the curing stage, the quaternary polymer is insolubilized. In the case of a photographic film the application of such a coating in this manner not only preserves the antistatic behavior of the coating, but the tackiness at high humidities is greatly reduced.

The following examples will demonstrate certain pre- :ferred embodiments of our invention, but are not to be considered to be limiting.

EXAMPLE I 'Poly-4-vinylpyridine was quaternized to the extent of 50 mole percent with dimethylsulfate by heating the ingredients together in methanol, using the proportions indicated. The solids content of the resulting solution was 25 percent by weight.

The following data are illustrative of other runs carried out with partially quaternized poly-4-vinylpyridine. A one percent solution of poly-4-vinylpyridine, 50 percent quaternized with dimethylsulfate in a 35 acetonez65 methanol solution, was coated onto a cellulose acetate film base. Additional coatings were made of this same solution to which was added an acetone solution of 1,4- bis-(methanesulfonoxy)-butyne to the extent of 5, 10, and 20 percent of the weight of the polymer. The results listedbelow show some of the effects and properties of such procedure.

I In the above example we have referred to a resistivity test. A value below 1.0 10 ohms/sq./cm. in such test indicates that for film the antistaticproperties would be quite satisfactory. This value is measured by a surface electrical resistance measuring apparatus. This appara-- tus is built around a megohmmeter type 1020, manufactured by the Freed Transformer Company, New York, and it is designed to operate within a resistance range of 10 to which is indicated by, the position of-the sensitivity selector switch on the megohmmeter. The electrodes used for this test consist of two steel plates 10 cm. in length and 0.5 cm. apart. Surface resistivity is defined as follows:

R=true resistance measured on the megohmmeter p=surface resistivity measured in ohms W=distance betweenelectrodes (0.5 cm.)

L =length of electrodes in contact with the sample (10 Hence, for the apparatus described, the surface resistivity of any sample can be determined by multiplying Y 4 the true resistivity, measured on the instrument, by a factor of 20.

In use the sample whose surface resistivity is to be determined is held in contact with the aforementioned electrodes by a spring loaded metal bar. A 500 volt direct current charge is fed into the apparatus and the reading on the megohmmeter together with the sensitivity factor are noted. This figure is then multiplied by 20 to give the surface resistivity of the sample.

The test for tackiness referred to above was as follows:

Two 70 mm. wide coated support samples are conditioned for 16 hours at 65 percent RH. and then pressed together back-to-front for an additional 24 hours under 6 lb./in. pressure. The two pieces are then separated by sliding an 0.040 inch diameter piano wire between them and the pull or force on the wire necessary to separate the layers is taken as a measure of the tackiness of the coating.

These data show that:

(1) Increasing amounts of the cross-linking agent cause insolubility of the polymer coating.

(2) Increasing amounts of the cross-linking agent are effective in reducing tackiness.

EXAMPLE II Similar results to those above have been obtained with samples of poly-4-vinylpyridine which were percent quaternized with dimethylsulfate. The amounts of crosslinker added were 0, 4 and 8 percent of the weight of the polymer.

EXAMPLE III A copolymer of B-methacryloxyethyltrimethylammonium methosulfate and fi-methacryloxyethyldiethylamine was prepared by copolymerizing the monomers in a 50/50 methanol/water solution in a 80:20 molar ratio at 50 C. using one percent of hydrogen peroxide as catalyst. The viscous solution was diluted with methanol and poured into a large volume of agitated acetone. The precipitate was washed with acetone and dried.

This copolymer was made into a 5 percent solution in methanol. Solutions were prepared which contained 2, 4 and 8 percent added 1,4-bis-(methanesulfonoxy)-butyne on the weight of the polymer. Films of these solutions were coated, and the solvent evaporated off at 60 C. Attempts to redissolve any of the films from solution containing cross-linker showed them to be insoluble, while the check coatings without added cross-linker readily redissolved. The insolubility and resistance to swelling increased with increasing amounts of the added cross-linker. Although as referred to above the preferred embodiment of this instant invention is a cross-linked antistatic layer essentially comprised of a quaternized dialkylaminoalkyl acrylate, various other polymers may be treated in a similar manner. Illustrations of such other polymers will be setforth hereinafter. The manner of coating the preferred polymer onto film, either color film or other web product, the solvents which may be used and other aspects may be the same as fully described in the aforementioned Thompson and Lyons patent. Hence, description of such features herein is unnecessary.

We have further found that a class of polymers containing quaternary pyridine groups as a part of their structure are very effective as antistatic agents and may be cross-linked. This type of polymer is capable of some variation and this is illustrated in the following examples. For instance, a polymer capable of being quaternized by reaction with pyridine, quinoline, isoquinoline or their derivatives may be used to give a quaternary polymer. Thus, a polyvinyl methanesulfonate, benzenesulfonateor p-toluenes'ulfonate may be allowed to'react'with'pyridine, a methylpyridine, aminopyridine, etc. to give. the corresponding quaternary polymer. In a similar manner, sulfonates of cellulose or starch may also be quaternized with pyridine derivatives. Furthermore, partial esters,

ethers or acetals of polyvinyl alcohol or cellulose may be esterified with a sulfonyl chloride and then quaterriized with pyridine. l

As another variant, homopolymers or copolymers of vinyl-pyridine monomers such as 2-viny1- and 4-vinylpyridine may be treated with various quaternizing agents su h as elky h lid s alto su fate n n tes or arallcyl halides where the halides are activated by the presence of activating substituents.

Furthermore, the monomeric vinylpyridine may be quaternized with a suitable quaternizing agent, then polymerized or copolymerized with various comonomers. Readily available vinylpyridine monomers include 2-vinylpyridine, 4-vinylpyridine and 2-methyl-5-vinylpyridine.

The following examples are illustrative of some of these other polymers which may be used for antistatic coatings.

EXAMPLE IV 1-Methyl-4-Vinylpyridinium p-Toluenesulfonate The following mixture was prepared:

160 g. of freshly distilled 4-vinylpyridine 295 g. of methyl p-toluenesulfonate 1200 ml. of ethyl acetate The solution began to precipitate crystals about one minute after mixing and the temperature gradually rose to 40-45 C. as a heavy crystalline paste was formed. After standing overnight at room temperature, the crystals were collected by filtration under suction and rinsing with a little ethyl acetate. The product was recrystallized by the addition of anhydrous ethyl acetate to a concentrated solution of the crystals in chloroform. White, finely divided crystals were formed which were filtered off and dried in vacuo. This crystalline monomer may then be polymerized by conventional procedures, in water or water-alcohol mixtures, in the presence of vinyl polymerization catalysts, such as hydrogen peroxide. If desired, the polymeric 1-methyl-4-vinylpyridinium p-toluenesulfonate may be isolated by pouring the solution into a large volume of a nonsolvent for the polymer, such as acetone. Such product may be coated onto film as an antistatic backing as already indicated above.

EXAMPLE V Preparation of Polymers and copolymers of 1j-Methyl-4- Vinylpyridinium pfToluenesulfonate With Styrene In the following table is described the preparation of a series of copolymers of 1-methyl-4rvinylpyridinium p-toluenesulfonate (MVPT) with styrene as well as an example of a homopolymer.

Run Sample Grams Grams Grams Solvent Temper- No. No. MVPT styrene B2202 e m1. ature, C.

2. 1610 14. 5 5.2 0.10 60 60 3 1611) 11.6 2. 1 0.07 50 60 161E 13.0 1.6 0.08 45 60 16113: 10. 0. Q 30 G0 EXAMPLE VI A solution of quaternary polymer whose preparation was described in Example Vrun 2 was prepared by weighing out 100 mg. of the dry polymer and adding 20 ml. of methanol. After solution was complete, the solution was pouredover a cellulose triacetate film base material which contained an abrasion resistant backing. The

6 solvent was evaporated off by hanging the sample in a vertical position in an air oven at 150 C. for a few minutes. The appearance of the coating was good.

Surface conductivity measurement was made by applying a potential of 500 volts to surface electrodes separated by 0.5 cm.

The resistivity observed was 6.1 X 10 ohms. Run 3--resistivity of 3.4)(10 ohms. Run 4-.resistivity of 2.4 X 10 ohms. Run 5- resistivity of 1.7-)(10 ohms.

1 Resistivity values are considered close enough to 1.O 1O ohms to indicate satisfactory use at slightly higher coverages.

EXAMPLE VII 1,Z-Dimethyl-S-Vinylpyridinium M ethosulfate A solution of 600 g. of freshly distilled Z-methyl-S: vinylpyridine and 1800 g. of acetone in a 5 l. three-neck flask fitted with a stirrer, condenser and dropping funnel was cooled externally with an ice-water mixture. To the cold stirred solution was added dropwise 700 g. of dimethyl sulfate (freshly distilled). The reaction temperature was kept at 15-20" C., out towards the end of the addition the temperature was allowed to rise to 40 C. The reaction product was allowed to stand for about /2 hour and then the white crystalline sludge was filtered by suction. The material was recrystallized by rapidly dissolving it in about 2 l. of boiling ethanol while heating. As soon as solution was complete, it was rapidly cooled. The crystals were filtered off, washed with a little cold ethanol and dried in a vacuum at room temperature. The

Solids (percent): Resistivity (ohms) 10 2 -"ave-e.

EXAMPLE VIII Poly-1,Z-Dimethyl-S-Vinylpyridinium M ethosulfate (Alternate Preparation of Example VII) Instead of first preparing the quaternary monomer and then polymerizing it, the final polymer may be prepared by a concomitant quaternization and polymerization of the 2'-methyl-5-vinylpyridine.

A solution of 36 g. of 2-methyl}5-vinylpyridine in ml. of isopropyl alcohol was mixed with a solution of 51 g. of dimethyl sulfate in 50 ml. of isopropyl alcohol. The resulting solution became warm and the isopropyl alcohol began to boil gently- The solution was refluxed by heating. on a steam bath and in three hours a. viscous pale yellow solution. had formed.

The above solution. was diluted with 100ml. ofiso-- propyl. alcohol and then poured slowly into seven liters. of agitated acetone. The fibrous precipitate was leached twice in fresh: acetone, filtered oif, and. dried invacuo; The product. was .very hygroscopic.

The appropriate amount of solid polymer was weighed. out to prepare the solutions in methanol at .64, 1.28, and 2.56' percent solids. Film was coated and tested with the following.

Percent-solids: Resistivity (10 ohms -In a 00-ml.'fiask were placed 50 g. of 1,2-dimethyl-5- vinylpyridinium methosulfate, 1.5 ml. of 30 percent hydrogen peroxide and 120 ml. of distilled water. The air above the reaction mixture was flushed with nitrogen, the flask stoppered, and placed in a bath at 60 C. During the initial warm-up, the pressure was occasionally relieved by lifting the stopper. At the end of 24 hours in the bath, a viscous solution had formed, which was removed from the bath and sent, as is, for use as an antistatic agent.

This polymer was diluted from a 30% solids solution in methanol to 1.05% solids in a 30% acetone-70% methanol mixture. This solution also contained a dye (sulfo rhodamine B) for coverage measurement. Five hundred milliliters of this solution was used for coating cellulose acetate film base by means of a bead application on a coating machine. The appearance of the coating was entirely satisfactory.

Surface resistivity measurement gave a value of .15 X ohms.

EXAMPLE X Poly-I-Ethyl-4-Vinylpyridinium Ethosulfate The following solution was heated at 50 C. for three days under an atmosphere of nitrogen:

200 g. 4 vinylpyridine 400 g. warm water 2.0 g. potassium persulfate (dissolved in a little water) 400 g. isopropyl alcohol To the pale amber, viscous solution was added with stirring (and while maintained in 50 bath) a solution of 293 g. of diethyl sulfate and 293 g. isopropyl alcohol). The mixture was stirred for /2 hour, then allowed to stand at 50 C. for 5 /2 hours. The product was diluted with enough water to give 3290 g. of solution containing 14% solids. As in the above examples, the polymer was dissolved, coated and tested except that the following amounts were used.

Stocks MeOH Sollds (ml.) (m1.) (Percent) Surface resistivity measurement gave the following value.

Percent solids: Resistivity (10 ohms EXAMPLE XI Quaternary Solvent Sample No. Styrene (g.) mo1oner B1202 (g.) (1111.)

Solutions of these polymers were prepared by dissolving .75 g. of the appropriate polymer in 18 ml. methanol. Six milliliters of this solution was then diluted to 50 ml. with methanol, coated and tested.

' Surface resistivity measurement as in Example VI gave the following values:

Polymer Percent Resistivity solids (10 ohms To a solution of g. of freshly distilled 4-vinylpyridine in 100 g. of isopropyl alcohol and 100 g. of water was added a solution of 1.0 g. of potassium persulfate dissolved in a little warm water. The solution was heated at 60 C. under a nitrogen atmosphere. After 24 hours the tan viscous product was cooled and to it was added dropwise a solution of g. of freshly distilled dimethyl sulfate in 120 g. isopropyl alcohol. The temperature rose and after some time, a soft cake precipitated out. After standing at room temperature overnight, the supernatent liquid was decanted and about 600 ml. of methanol was added. The solution formed was poured in a thin stream into a large volume of agitated acetone. The precipitate was leached in fresh acetone, then dried in vacuo at room temperature.

Coating solutions of this polymer were prepared at 1.05% solids in the following ratios of acetone and methanol 10:90, 30:70 and 50:50. These solutions were coated on a machine as described above.

Surface resistivity measurement yielded values in the range of .018-.02 10 ohms.

EXAMPLE XIII Copolymers of Methyl Methacrylate With 4-Vinylpyridinium Methosulfate A series of copolymers of freshly distilled 4-vinylpyridine and methyl methacrylate were prepared using the proportions indicated in the following table:

After polymerizing at 60 overnight, the solutions were allowed to stand at room temperature another day. To each of the solutions was then added a solution of a molar equivalent of freshly distilled dimethyl sulfate in methanol (based on the 4-vinylpyridine present), and then allowed to stand at room temperature for three days. Each of the solutions were then diluted with methanol and this solution was poured in athin stream into a large volume of acetone. The precipitate was then leached in fresh acetone and dried in vacuo.

Solutions of these copolymers were prepared in various solvent ratios and coated as already described.

Surface resistivity measurements gave the following values.

While the butyne described above represents one of our preferred cross-linkers, as indicated, other cross-linkers may be used. The following examples will further illustrate this.

9 EXAMP E X {I116 rass-l nk i s afie nselubi i i .Wa ,u' dibromo-p-xylene. This was coatedwith poly-ety py i which 80 Percent uat rh d w h dimethyl sulfate. The results below show some of the ef t thss bs r in insbrdriiop-xylene causes the aritistatic'coating to resist removalby washing'offf XAMPLE X The cross-linker used to effect insolubilization was bis-(methanesulfonoxy)pentane. This was added to the polymer as aboye.

Concentration of Surface re- R 10 Sample No. cross-linker eistivity after as coated washing 0.1% theoretical amount"... 2.0 2. 7 1.0% theoretical amount 3. 8 64 0% theoretical amount 1. 1 1,000

The resistivity data indicate the permanence of the antistatic coating with respect to solubility in water.

. EXAMPLE XVI Using the procedure described under Example I, a coating wa's'made on'tlie' back of seamless triacetate photographic filinhisinga solution 0190.3 part of a poly fL vinylpyridine, which"ha'd been quaternized to the extent of about 80 mole percent with dimethyl sulfate, in 100 parts of a 2:3 ratio of acetone-methanol. Immediately before coating, there was added 0.1 part of diglycidyl ether to the solution. The coated film was cured in a heated air section at 180 F. for about 5 minutes. The film displayed a surface resistivity of 0.8 ohms. After washing in cold water for 5 minutes, this resistivity was virtually unchanged. In contrast, a similar coating made without the addiiton of the diglycidyl ether, while showing a conductivity approximately that indicated above, possessed a resistivity value several orders higher after washing for 5 minutes.

Instead of diglycidyl ether, there may be substituted other biand polyfunctional epoxides, such as diglycidyl ethers of various glycols, butadiene dioxide, low molecular weight epoxy resins, as well as polymers containing polymerized glycidyl acrylate and methacrylate units.

It can be seen from the foregoing examples that we have shown a number of polymeric backings which may be applied to various types of film support carrying various types of light-sensitive layers. That is, the antistatic backings of the present may be applied to the several types of film base described in detail in the Thompson and Lyons patent. The finished backed film product may be motivated in various manners, rolled tightly upon itself and otherwise subjected to different tests and usage. As already im'dcated above, our new backing reduces static and is non-injurious to the light-sensitive layers even when the film is tightly rolled upon itself. The tackiness of the backing is very low.

While the preferred embodiment of our invention comprises applying the cross-linked combination of materials set forth in certain examples of the present application, in the broader concepts our invention is not thus limited to these exact cross-linking agents. The solvents and proportions may be generally as described above or as set forth in Thompson and Lyons.

The invention has been described in detail with particu- 1 arreference ,to preferred embodiments thereof, but it will "be understood that variations and modifications can be effected within the spirit and scope of the invention as describedliefeinabove and as defined in the appended l v r 1 im= 1. 'Ap'hotographic film product comprised of (A) a relatively nonporous film support, (B) at least one light} sjensitiye silver lialideemulsio'n layer on one surface of'the" support, and '(Cfabacking layer on the other surface of the support, 'said backing layer being confprised of the product derived bycr'osslinking a 50% to quaternized""tertiary amino-containing polymeric materia1"witl1" a polyfunctional erosslinking agent containing-a pluralityof groups reactive to form quaternary ammonium linkages "with the unquaternized tertiary amino groups of the polymeric'material.

2. 'A photographic film product comprised of (A) a relatively non-porous film'support, (B) at least one light sensitive silver halide emulsion layer on one surface of the support, and (C) a backing layer on the other surface of the support, said backing layer being comprised of the product'derived by crosslinking a 50% to 80% quaternized tertiary amintrcontaining polymeric material with a polyfunc tional quaternizing agent'capable of reacting with the unquaternized tertiary amino groups of the polymeric material selected from the group con 'sjist llg 0f'apolyepoxide, a xylylene dibromide, a bis: alkylsulfonoxy alkane, a bis-arylsulfonoxy alkane, a bis: alkylsiilfonoxy alkene, a bis-arylsulfonoxy alkene, a bis alkylsulfonoxy alkyne, and'a'bis-arylsulfonoxy alkyne.

3i A photographic film product comprised of (A) a. relatively nonporous filmsupport, (B) at least onelight-sensitive silver halide emulsion layer on one sur face of the support and (C) abacking layer on the other surfaceof the support, said backing layer com; prising the product derived by crosslinking a 50% to 80% quaternized tertiary amino-containing polymeric material selected from the group consisting of a quaternized dialkylaminoalkyl acrylate polymer and a quaternized polyvinylpyridine polymer with a polyfunctional quarternizing agent capable of reacting with the unquaternized tertiary amino groups of the polymer selected from the group consisting of a polyepoxide, a xylylene dibromide, a bis-alkyl sulfonoxy alkane, a bis-arylsulfonoxy alkane, a bis-alkylsulfonoxy alkene, a bis-arylsulfonoxy alkene, a bis-alkylsulfonoxy alkyne, and a bisarylsulfonoxy alkyne.

4. A photographic film product comprised of (A) a relatively non-porous film support, (B) at least one lightsensitive silver halide emulsion layer on one surface of the support and (C) a backing layer on the other surface of the support, said backing layer comprising the product derived by crosslinking 50% to 80% quaternized poly-fl-methacrylyl-oxyethyldiethylmethyl ammonium methylsulfate with a polyfunctional quarternizing agent capable of reacting with the unquarternized tertiary amino groups of the polymer selected from the group consisting of a polyepoxide, a xylylene dibromide, a bis: alkylsulfonoxy alkane, a bis-arylsulfonoxy alkane, a bisalkylsulfonoxy alkene, a bis-arylsulfonoxy alkene, 2. bisalkylsulfonoxy alkyne, a bis-arylsulfonoxy alkyne.

5. A photographic film product comprised of (A) a relatively non-porous film support, (B) at least one lightsensitive silver halide emulsion layer on one surface of the support and (C) a backing layer on the other surface of the support, said backing layer comprising the product derived by crosslinki ng a 50% to 80% quaternized polyvinylpyridine polymer with a polyfunctional quaternizing agent capable of reacting with the unquarternized tertiary amino groups of the polymer selected from the group consisting of a polyepoxide, a xylylene dibromide, a bis-alkylsulfonoxy alkane, a bis-arylsul fonoxy alkane, a bis-alkylsulfonoxy alkene, a bis-aryl- 11 'sulfonoxy alkene, a bis-alkysulfonoxy alkyne, and a hisarylsulfonoxy alkyne. V

6. A photographic film product comprised of (A) a relatively non-porous film support, (B) at least one lightsensitive silver halide emulsion layer on one surface of the support, and (C) a backing layer on the other surface of the support, said backing layer comprising the product derived by crosslinking a 50% to 80% quaternized dialkylaminoalkyl acrylate polymer with a polyfunctional quaternizing agent capable of reacting with the unquaternized tertiary amino groups of the polymer selected from the group consisting of a polyepoxide, a xylylenedibromide, a bis-alkylsulfonoxy alkane, a bisarylsulfonoxy alkane, a bis-alkylsulfonoxy alkene, a bisarylsulfonoxy alkene, a bis-alkylsulfonoxy alkyne, and a bis-arylsulfonoxy alkyne.

7. A photographic film product comprising (A) a relatively non-porous support, (B) at least one lightsensitive silver halide emulsion layer on one surface of the film support, and (C) a backing layer on the other surface of the film support, said backing layer comprising the product derived by crosslinking 50%-80% quaternized poly-fl-methacrylyloxyethyldiethylmethyl ammonium methylsulfate with l,4-bis-(methanesulfonoxy)- butyne.

8. A photographic film product comprised of (A) a relatively non-porous film support, (B) at least one lightsensitive silver halide emulsion layer on one surface of the film support, and (C) a backing layer on the other surface of the film support comprising the product derived by crosslinking 50% to 80% quaternized poly-phiethacrylyloxyethyldiethylmethyl ammonium methylsulfate with bis-(methanesulfonoxy)pentane.

9. A photographic film product comprised of (A) a relatively non-porous film support, (B) at least one lightsensitive silver halide emulsion layer on one surface of the film support, and (C) a backing layer on the other surface of the filrn support comprising the product derived by crosslinking to quaternized polyfi-methacrylyloxyethyldiethylmethyl ammonium methylrivedvby crosslinking a 50% to 80% quaternized polyvinylpyridine polymer with l,4-bis-(methanesulfonoxy)- butyne.

11. A photographic film product comprised of (A) a relatively non-porous film support, (B) at least one lightsensitivesilver halide emulsion layer on one surface of the film support, and (C) a backing layer on the other surface of the film support comprising the product derived by crosslinking a 50% to 80% quaternized polyvinylpyridine polymer with bis-(methanesulfonoxy) pentane.

12. A photographic film product comprised of (A) a relatively non-porous film support, (B) at least one lightsensitive silver halide emulsion layer on one surface of the film support, and (C) a backing layer on the other surface of the film support comprising the product derived by crosslinking a 50% to 80% quaternized polyvinylpyridine polymer with a,a'-dibromo-p-xylene.

References Cited in the file of this patent UNITED STATES PATENTS 2,279,410 Nadeau et al. Apr. 14, 1942 2,631,993 Morgan Mar. 17, 1953 2,838,397 Grunfest June 10, 1958 2,843,562 Caldwell July 15, 1958 2,882,157 Thompson et al. Apr. 14, 1959 

1. A PHOTOGRAPHIC FILM PRODUCT COMPRISED OF (A) A RELATIVELY NON-POROUS FILM SUPPORT, (B) AT LEAST ONE LIGHTSENSITIVE SILVER HALIDE EMULSION LAYER ON ONE SURFACE OF THE SUPPORT, AND (C) A BACKING LAYER ON THE OTHER SURFACE OF THE SUPPORT, SAID BACKING LAYER BEING COMPRISED OF THE PRODUCT DERIVED BY CROSSLINKING A 50% TO 80% QUATERNIZED TERTIARY AMINO-CONTAINING POLYMERIC MATERIAL WITH A POLYFUNCTIONAL CROSSLINKING AGENT CONTAINING A PLURALITY OF GROUPS REACTIVE TO FORM QUATERNARY AMMONIUM LINKAGES WITH THE UNQUATERNIZED TERTIARY AMINO GROUPS OF THE POLYMERIC MATERIAL. 